North Korea says it will permanently ‘shut off’ border with South

North Korea said it would permanently seal its border with South Korea and cut off all roads and railways linking the neighbouring countries but stopped short, for now, of formally declaring Seoul its chief enemy.

Pyongyang would “permanently shut off and block the southern border”, the official KCNA news agency reported, adding it would " fortify the relevant areas of our side with strong defence structures”.

The military called it a " self-defensive measure for inhibiting war and defending the security" of North Korea as "the hostile forces are getting ever more reckless in their confrontational hysteria”.

It was unclear how the decision would impact relations with South Korea, analysts said, given that travel and exchanges across the border had been suspended for years.

The decision came as the North’s parliament, the Supreme People’s Assembly, convened this week to announce key decisions. It was expected to formally change the country’s constitution to declare South Korea its "invariable principal enemy".

North Korean leader Kim Jong-un declared South Korea “ No 1 enemy ” early this year and said Pyongyang would no longer seek reconciliation and reunification with it.

Analysts were watching if the North would assert legal claims over the waters controlled by South Korea off its west coast. The poorly defined maritime boundary has been the site of several bloody naval skirmishes over the past 25 years.

Some experts suspected that North Korea might have delayed the constitutional revision while others speculated it had already amended the document without publicising it because of its sensitivity.

South Korea’s Joint Chiefs of Staff said on Wednesday they would not tolerate any attempt by the North to change the status quo on the border.

The South would “overwhelmingly punish” the North if it launched any provocation, it said in a statement.

Pyongyang’s latest decision, it claimed, was “a desperate measure stemming from the insecurity of the failed Kim Jong-un regime” and would “only lead to its harsher isolation.”

The South earlier said the North had been placing anti-tank barriers and reinforcing roads on its side of the border since April in a likely attempt to boost its frontline security posture and prevent its citizens from defecting away.

In a report to the parliament on Tuesday, South Korea’s Unification Ministry said that North Korea had been removing linkages on its side of the crossborder railways and planting mines.

Tensions have been rising on the Korean peninsula in recent years with the North continuing a run of weapons tests and the South expanding their military drills with the US.

The tensions spiralled earlier this year after the North dropped thousands of balloons filled with trash on the South in retaliation for the South sending across balloons filled with propaganda material.